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The inherently poor capacity of post-neonatal vascular smooth muscle cells (SMCs) to synthesize elastin and biomimetically assemble elastic matrix structures is a major limitation to our present ability to tissue engineer functional vascular replacements. Therefore, we presently seek to ascertain if SMCs freshly differentiated from bone marrow mesenchymal stem cells (BM-MSCs), are elastogenically superior or comparable to mature, adult aortic SMCs, which would justify their use as elastogenic cell sources for vascular tissue engineering. We also seek to determine as to how BM-MSCs differentiation protocols influence the quality and quantity of elastic matrix deposition. Rat BM-MSCs treated with PDGF-BB (50 ng/mL) and TGF-β1 (5 ng/mL), were differentiated on human fibronectin (hFN) coated wells for 7 and 14 days respectively and number-expanded in the presence of factors for 7 days in uncoated flasks. Immunohistochemistry data for SMC specific markers showed positive staining for α-SMA in PDGF-BB and TGF-β1 (7 and 14 day) treated BM-MSCs compared to controls where as all the cultures expect expressed Calponin BM-MSCs treated without cytokines for 7 days. Quantitative analysis revealed that α-SMA is more intensely expressed per cell in PDGF-BB treated BM-MSCs for 7 days when compared to the other conditions, whereas, TGF-β1 treated BM-MSCs for 14 days had the highest intensity of antibody per cell for Calponin. Flow cytometry results indicated that BM-MSCs differentiated with TGF-β1, especially for 14 days more intensely express SMC markers, especially a-SMA compared to other markers. Cell cycle analysis indicated that hFN-coated substrate doesnot affect differentiation capacity or BM-MSCs and treated with TGF-β1 exhibit a greater number of cells in the G1 phase of the cell cycle compared to PDF-BB-treated BMMSCs. Real time polymerase chain reaction (RT-PCR) data show higher expression of α-SMA, SMMHC and LOX in BM-MSCs differentiated for 7 and 14 days with and without cytokines compared to BM-MSCs and the greatest expression in BM-MSCs differentiated in the absence of cytokines for 14 days. Elastin gene expression was greatest in the 14 day TGF- β1 treated cultures and there was no difference in gene expression between treatment or control groups for Caldesmon. Cell proliferation data showed that 7 day differentiation groups had lower cellular proliferation and BM-MSCs treated with PDGF-BB and TGF-β1 for 14 days had lower expression compared to others. Comparing the effect of differentiation time, those cultured for 14 days showed lower cellular proliferation in all groups except SMCs. Like wise, fold change data exhibited that TGF-β1 treated BM-MSCs for both 7 and 14 days were far less proliferative than any other group. BM-MSCs treated with PDGF-BB produced greater amounts of insoluble and soluble elastin compared to all other groups. No significant differences between BM-MSCs treated and untreated with cytokines for 7 and 14 day and control cell lines were found in the amounts of collagen and LOX activity except SMCs.